Anti-Hunger Smells Could Battle Obesity

Anti-hunger aromas that make one feel full could help fight the global obesity epidemic, scientists now suggest.

Everyone
is familiar with scents that arouse the appetite, as well as odors that
turn the stomach. But apparently molecules that make up a food's aroma
can also activate areas of the brain that trigger the feeling of
fullness.

As people chew food, scents wafting up to the back of
the nose from inside the mouth help quench the sensation of hunger,
food technologist Rianne Ruijschop at NIZO Food Research in Ede, The
Netherlands, and her colleagues found.

When
odors linked either with fat, carbohydrates or proteins were tested,
adding scents linked with carbohydrates or protein significantly
increased the feeling of fullness, perhaps because they suggest food is
high in energy.

Complex aromas with multiple
components were more filling than others with just one component.
Complex aromas might tell the brain it's eating a variety of food and
thus a large meal.

The size of food samples had an impact, as smaller bite sizes prolonged the amount of time in which odors could have an effect.

In
experiments, the researchers could modify how filling various foods
were. For instance, making a beverage release aromas much like solid
foods would significantly increased the feeling of fullness.

Feeling full

These
findings could help researchers develop a new generation of foods that
release aromas that help people feel full, therefore fighting
overeating and obesity. Scientists might add capsules that boost or
prolong aftertaste or release of aromas. They might also introduce
chewy ingredients, or reduce bite size to increase the amount of
chewing people have to do. Complex odors could be added, as well as
scents that suggest the food is rich in energy.

In recent,
as-yet unpublished work, Ruijschop said that by controlling aroma, they
could in fact lower the amount of food people consumed by roughly 10
percent. They are now conducting long-term studies to see what effects
months of changes in aromas can have on people.

Although aromas
could contribute to the fight against obesity, "they're not really the
solution by itself," Ruijschop noted. "It's also very much about
changes in lifestyle."

Ruijschop and her colleagues detailed their findings in the November 11 issue of the Journal of Agricultural and Food Chemistry.

Charles Q. Choi

Charles Q. Choi is a contributing writer for Live Science and Space.com. He covers all things human origins and astronomy as well as physics, animals and general science topics. Charles has a Master of Arts degree from the University of Missouri-Columbia, School of Journalism and a Bachelor of Arts degree from the University of South Florida. Charles has visited every continent on Earth, drinking rancid yak butter tea in Lhasa, snorkeling with sea lions in the Galapagos and even climbing an iceberg in Antarctica.